If a diamond symbolizes commitment, promise and love, does that mean a faux diamond represents infidelity or dislike? What would you do if you purchased a piece of diamond jewelry, only to find out later you dropped thousands of dollars on a synthetic stone worth a fraction of that price?
No one wants to be deceived but, unfortunately, there are unscrupulous sellers out there who will sell you a fake diamond under the pretense of it being real. To protect yourself, there are a few ways you can test a stone before making a purchase to ensure you’re getting the “real deal.”
Buying a Diamond
- Certification–Ask the jeweler for a certificate for the stone. Most independent jewelers or chain stores should be able to provide you with a diamond report or a certificate from a highly-regarded laboratory like the Gemological Institute of America (GIA), which will prove the authenticity of the stone. Make sure you receive a certificate from a laboratory and not a simple “certificate of authenticity” created by the jewelry store itself. Shifty jewelers may create a certificate with fabricated grades for diamonds to make it look like you get a better stone than what you actually receive.
- Laser Inscription–Find out if the diamond is laser inscribed with an ID number or other identifying mark. An inscribed ID number corresponds to a stone’s certification, ensuring its authenticity. These marks are inscribed on the diamond at the lab where it is graded, making sure the diamond will always be linked to its own paperwork.
These are two excellent methods to ensure you purchase a new, authentic diamond; but, what if you want to test the diamond in your great-grandmother’s heirloom necklace? There are several DIY tests you can run on your own to determine if the stone is genuine.
DIY Tests for Loose Diamonds
- Dot Test—Using a ballpoint pen, draw a small dot on a piece of white paper. Flip the diamond upside down onto its table and center it over the dot. A natural diamond will break up the reflection, making it nearly impossible to see the dot through the stone. A Cubic Zirconia (CZ) will look more like a piece of glass and you will be able to easily see the dot beneath it.
- Precision Test—A precision scale will allow you to weigh the diamond, helping you determine whether or not the stone is real. A 1.0 carat diamond weighs 200 milligrams; a CZ of the same size weighs about twice that amount. This isn’t the most accurate test for determining the authenticity of a diamond, especially if your stone is not exactly 1ct., or if you are unsure of the stone’s actual size.
- Diamond Tester—If you have access to one, a diamond tester can be a fairly good way to test the validity of your stone. Traditional testers measure the electrical and thermal conductivity of the stone, while more advanced testers also measure reflectivity. You should test both electrical and thermal conductivity of the stone because the synthetic diamond Moissanite has the same thermal conductivity as a diamond; however, it’s electrical conductivity is different.
DIY Tests for Mounted or Loose Stones
- Scratching or Scuffing—Let me be clear: you should NOT purposely scratch or scuff your stone. You don’t want to cause unnecessary damage to your gem regardless of whether or not it’s real. However, if you have a vintage piece of jewelry, you can examine the surface of the stone for scuffs or scratches. A CZ that was worn regularly will show marring on its surface, while a real diamond will not.
- Breath Test—Natural diamonds are great heat conductors, so if you breath on the table of the diamond (like you would if you were fogging a mirror), an authentic diamond will clear almost immediately. Unfortunately, since Moissanite conducts heat like a diamond, this is not a finite test for determining the validity of your stone.
- Magnification—If your stone passed the breath test, you can determine whether or not it’s Moissanite by using a microscope or jeweler’s loupe. Simply look at the gemstone under magnification through one of the bezel or star facets on the crown. If you see what appears to be double lines of each facet, your stone is probably Moissanite. The magnifier can also be used to examine the girdle of the stone. Real diamonds will have either a frosted, grainy look or show small facets, while a CZ appears to be completely smooth.
Ultimately, the best way to determine whether or not the stone you have on hand is real is to take it to a professional. Search around and find a reputable gemologist for an appraisal of your stone. Make sure they are worthy of reviewing your stone by checking online reviews or their company’s Better Business Bureau Rating.